[pkg-cryptsetup-devel] Bug#533643: lacks superblock backup

[Goswin Brederlow]

Package: cryptsetup
Version: 2:1.0.6+20090405.svn49-1
Severity: normal

Hi,

I just lost 1.5TB data because I accidentally installed grub over the
LUKS superblock and there seems to be no way to restore it.

I'm missing 2 things:

1) an on disk backup of the superblock
   That would not only help with accidental overwrites but also if a
   block gets damages on the disk.
   
   It might also be a good idea to move the superblock 4k or 64k from
   the start of the device so a mbr/bootloader does not overwrite the
   superblock.

2) cryptsetup luksBackup and luksRestore command
   There should be a command to dump the superblock of a luks volume
   into a file for backup purposes and one to restore it from a file.
   cryptsetup could even automatically store a backup on every change
   like lvm does.

MfG
	Goswin

-- System Information:
Debian Release: squeeze/sid
  APT prefers transitional
  APT policy: (500, 'transitional'), (500, 'unstable'), (400, 'unstable-i386'), (1, 'experimental-i386'), (1, 'experimental')
Architecture: amd64 (x86_64)

Kernel: Linux 2.6.29.4-frosties-1
Locale: LANG=C, LC_CTYPE=de_DE (charmap=ISO-8859-1)
Shell: /bin/sh linked to /bin/bash

Versions of packages cryptsetup depends on:
ii  dmsetup                      2:1.02.30-3 The Linux Kernel Device Mapper use
ii  libc6                        2.9-12      GNU C Library: Shared libraries
ii  libdevmapper1.02.1           2:1.02.30-3 The Linux Kernel Device Mapper use
ii  libpopt0                     1.14-4      lib for parsing cmdline parameters
ii  libuuid1                     1.41.6-1    Universally Unique ID library

cryptsetup recommends no packages.

Versions of packages cryptsetup suggests:
ii  dosfstools                    3.0.3-1    utilities for making and checking 
ii  initramfs-tools [linux-initra 0.93.3     tools for generating an initramfs
ii  udev                          0.141-1    /dev/ and hotplug management daemo

-- no debconf information